On 3/30/2011 1:11 AM, Gregori Schmidt wrote

I wouldn't call it a horrible mess but the learning curve for newcomers can be quite steep.   This said, having a common portable spec to program to (ie thrift) is a very good idea instead.

It's a fair concern.  But bugs are fixed in either upstream or minor releases (or even *shudder* maintenance patches...).  But that may be a small price to pay when you consider the headaches scaling out other systems (and don't you even think this will be un-problematic).

I would recommend that everyone interested in improving Cassandra take the day off,  download MongoDB and read https://github.com/karlseguin/the-little-mongodb-book . Then, while you are downloading, unpacking, looking at what was in the JAR, reading the book and pawing through the examples: _pay attention_ to the neatness and the effortlessness the ease with which you can use MongoDB.  Then spend the rest of the day implementing something on top of it to gain some hacking experience.

Arguably, the documentation is neat.  The scaling solution however, is not.  And that's the biggest headache.  Mongo should learn from cassandra in this respect.

No, really.  Do it.  This is important.  You need to connect with the user and you need to understand what you ought to be aspiring to.

Took you advice, done it.  You may be looking for a rdbms replacement -- and mongo may be a good solution there, but the master/slave replication setup puts me off.  That's a big nono for us and probably a lot of people on this list.

Considering the griefs of master/slave replication for scalability (oh, how have we been bitten by this one over the years),  I strongly applaud a project like cassandra to step up to the challenge and propel the free software community into 21st century scalability!  

Yes, the documentation could be better (it always can be), yes the Cassandra book by O'Reilly has a HUGE amount of duplication (speak unnecessary code/bad programming practice).   But the constructive thing to do here is to:

1 - CONTRIBUTE to the documentation (I was unhappy with the Exim and Windowmaker docs a looong time ago and my efforts did not go in vain)

2 - Direct your flame about to book on ora.com or amazon where this sort of feedback goes to the right channels, but don't blame the cassandra project for the shortcomings of the book.  That's someone else's problem ;)

3 - enjoy MongoDB.  Let us know how it scales.  Every project can learn from each other.

Happy Hacking!